}
} /* Namespace selftest. */
+
+/* Generate code to enable conditional branches in functions over 1 MiB.
+ Parameters are:
+ operands: is the operands list of the asm insn (see arm_cond_branch or
+ arm_cond_branch_reversed).
+ pos_label: is an index into the operands array where operands[pos_label] is
+ the asm label of the final jump destination.
+ dest: is a string which is used to generate the asm label of the intermediate
+ destination
+ branch_format: is a string denoting the intermediate branch format, e.g.
+ "beq", "bne", etc. */
+
+const char *
+arm_gen_far_branch (rtx * operands, int pos_label, const char * dest,
+ const char * branch_format)
+{
+ rtx_code_label * tmp_label = gen_label_rtx ();
+ char label_buf[256];
+ char buffer[128];
+ ASM_GENERATE_INTERNAL_LABEL (label_buf, dest , \
+ CODE_LABEL_NUMBER (tmp_label));
+ const char *label_ptr = arm_strip_name_encoding (label_buf);
+ rtx dest_label = operands[pos_label];
+ operands[pos_label] = tmp_label;
+
+ snprintf (buffer, sizeof (buffer), "%s%s", branch_format , label_ptr);
+ output_asm_insn (buffer, operands);
+
+ snprintf (buffer, sizeof (buffer), "b\t%%l0%d\n%s:", pos_label, label_ptr);
+ operands[pos_label] = dest_label;
+ output_asm_insn (buffer, operands);
+ return "";
+}
+
#undef TARGET_RUN_TARGET_SELFTESTS
#define TARGET_RUN_TARGET_SELFTESTS selftest::arm_run_selftests
#endif /* CHECKING_P */
;; And for backward branches we have
;; (neg_range - neg_base_offs + pc_offs) = (neg_range - (-2 or -4) + 4).
;;
+;; In 16-bit Thumb these ranges are:
;; For a 'b' pos_range = 2046, neg_range = -2048 giving (-2040->2048).
;; For a 'b<cond>' pos_range = 254, neg_range = -256 giving (-250 ->256).
+;; In 32-bit Thumb these ranges are:
+;; For a 'b' +/- 16MB is not checked for.
+;; For a 'b<cond>' pos_range = 1048574, neg_range = -1048576 giving
+;; (-1048568 -> 1048576).
+
(define_expand "cbranchsi4"
[(set (pc) (if_then_else
(match_operator 0 "expandable_comparison_operator"
(label_ref (match_operand 0 "" ""))
(pc)))]
"TARGET_32BIT"
- "*
- if (arm_ccfsm_state == 1 || arm_ccfsm_state == 2)
+ {
+ if (arm_ccfsm_state == 1 || arm_ccfsm_state == 2)
{
arm_ccfsm_state += 2;
- return \"\";
+ return "";
}
- return \"b%d1\\t%l0\";
- "
+ switch (get_attr_length (insn))
+ {
+ case 2: /* Thumb2 16-bit b{cond}. */
+ case 4: /* Thumb2 32-bit b{cond} or A32 b{cond}. */
+ return "b%d1\t%l0";
+ break;
+
+ /* Thumb2 b{cond} out of range. Use 16-bit b{cond} and
+ unconditional branch b. */
+ default: return arm_gen_far_branch (operands, 0, "Lbcond", "b%D1\t");
+ }
+ }
[(set_attr "conds" "use")
(set_attr "type" "branch")
(set (attr "length")
- (if_then_else
- (and (match_test "TARGET_THUMB2")
- (and (ge (minus (match_dup 0) (pc)) (const_int -250))
- (le (minus (match_dup 0) (pc)) (const_int 256))))
- (const_int 2)
- (const_int 4)))]
+ (if_then_else (match_test "!TARGET_THUMB2")
+
+ ;;Target is not Thumb2, therefore is A32. Generate b{cond}.
+ (const_int 4)
+
+ ;; Check if target is within 16-bit Thumb2 b{cond} range.
+ (if_then_else (and (ge (minus (match_dup 0) (pc)) (const_int -250))
+ (le (minus (match_dup 0) (pc)) (const_int 256)))
+
+ ;; Target is Thumb2, within narrow range.
+ ;; Generate b{cond}.
+ (const_int 2)
+
+ ;; Check if target is within 32-bit Thumb2 b{cond} range.
+ (if_then_else (and (ge (minus (match_dup 0) (pc))(const_int -1048568))
+ (le (minus (match_dup 0) (pc)) (const_int 1048576)))
+
+ ;; Target is Thumb2, within wide range.
+ ;; Generate b{cond}
+ (const_int 4)
+ ;; Target is Thumb2, out of range.
+ ;; Generate narrow b{cond} and unconditional branch b.
+ (const_int 6)))))]
)
(define_insn "*arm_cond_branch_reversed"
(pc)
(label_ref (match_operand 0 "" ""))))]
"TARGET_32BIT"
- "*
- if (arm_ccfsm_state == 1 || arm_ccfsm_state == 2)
+ {
+ if (arm_ccfsm_state == 1 || arm_ccfsm_state == 2)
{
arm_ccfsm_state += 2;
- return \"\";
+ return "";
}
- return \"b%D1\\t%l0\";
- "
+ switch (get_attr_length (insn))
+ {
+ case 2: /* Thumb2 16-bit b{cond}. */
+ case 4: /* Thumb2 32-bit b{cond} or A32 b{cond}. */
+ return "b%D1\t%l0";
+ break;
+
+ /* Thumb2 b{cond} out of range. Use 16-bit b{cond} and
+ unconditional branch b. */
+ default: return arm_gen_far_branch (operands, 0, "Lbcond", "b%d1\t");
+ }
+ }
[(set_attr "conds" "use")
(set_attr "type" "branch")
(set (attr "length")
- (if_then_else
- (and (match_test "TARGET_THUMB2")
- (and (ge (minus (match_dup 0) (pc)) (const_int -250))
- (le (minus (match_dup 0) (pc)) (const_int 256))))
- (const_int 2)
- (const_int 4)))]
+ (if_then_else (match_test "!TARGET_THUMB2")
+
+ ;;Target is not Thumb2, therefore is A32. Generate b{cond}.
+ (const_int 4)
+
+ ;; Check if target is within 16-bit Thumb2 b{cond} range.
+ (if_then_else (and (ge (minus (match_dup 0) (pc)) (const_int -250))
+ (le (minus (match_dup 0) (pc)) (const_int 256)))
+
+ ;; Target is Thumb2, within narrow range.
+ ;; Generate b{cond}.
+ (const_int 2)
+
+ ;; Check if target is within 32-bit Thumb2 b{cond} range.
+ (if_then_else (and (ge (minus (match_dup 0) (pc))(const_int -1048568))
+ (le (minus (match_dup 0) (pc)) (const_int 1048576)))
+
+ ;; Target is Thumb2, within wide range.
+ ;; Generate b{cond}.
+ (const_int 4)
+ ;; Target is Thumb2, out of range.
+ ;; Generate narrow b{cond} and unconditional branch b.
+ (const_int 6)))))]
)
\f